this weekend, the city will commemorate the event. we have been talking to some of the survivors. >> 70 years since the end of one of the world's bloodiest battles. the memorial remains one of the most symbolic sites in russia. here come close to a million soldiers died in just six months of ruthless combat. a breath-taking german advance into russia had been blocked at stalingrad. hundreds of thousands of men died in a brutal urban warfare as the red army refused to yield. then, once the russian winter set in, fresh soviet forces surrounded the entire army, killing or capturing every man. the german commander was forced into a humiliating situation. this man witnessed the surrender, but the images that etched most strongly on his memory are the images of death and a burning river. >> everything was on fire. the bank of the river was covered mixed with human heads, arms, legs. there are the remains of people who were being taken across when they were bombed. >> the scale of the loss of life is almost beyond imagination and it all happ